Engine starter



Dec, 118 9 1923..

v. BENDHX ENGINE smnwa 2 Sheets-Sheet )1 Filed Oct. 19 1922 :lllll: u a

44 ilQ Patented] I8, 119230 VINCENT BENDIX, F CHICAG K ILLINOIS.

ENGINE sran'rnn.

Application filed October 19, 1922. Serial No. 595,5tl1l.

I and more particularly to that part thereof known as the drive or transmission. In the present instance such invention is embodied in a drive of the Bendix type exemplified by a screw shaft which is rotated by an electric motor and on which is screwthreaded a driving member, such as a pin ion adapted to engage the engine member such as they fly-wheel of an internal combustion engine. The object of my invention is to. provide means for relieving the drive against any possible efiect of back-fire which causes a backward rotation of the flywheel and of the drive. In the present instance, the driving member is made in two parts, one a pinion proper and the other a control member or nut, and in carrying out my invention, I provide an additional member intermediate the fly-wheel and the nut which causes a backing off of the nut in case of backward rotation of the fly-wheel,

thereby relieving the drive and'motor of any strain.

In the drawings, Figure 1 is an elevation partly in section illustrating a starter system embodying my invention: Fig. 2 a similar view illustrating a portion of the part shown in Fig. 1 but showing the driving member in operating position; Fig. '3 an elevation of one face of the control member br nut Fig. 4 a section on the line 4.4 of Fig. Fig. 5 an elevation of the other side or face of such control member; and- Fig. 6 a plan View of a portion'of the brackets.

For the purpose of a clear and definite descriptionof my invention, I have shown the same embodied in a particular form and construction of drive or transmission, but it will he understood that in so far as my invention in its broader aspect is concerned other types and constructions of drive may be employed.

Referring to the particular construction shown in the drawings, an electric motor 1' has an extended armature shaft 2 on which the drive is mounted and by which it is operated. The drive comprises a driving head 3 secured to the shaft 2 by the bolt 4,

a hollow screw shaft 5 loosely mounted upon the rotatable driving shaft 2 and provided at its end with a stop nut 6, a driving mem- 00 her which here comprises a pinion 7 and a control member or nut 8, and a drive sp 9 operatively connecting the driving ri id 3 and the driving head 10 forming a part of the screw shaft, such spring being seca cured at its opposite ends to the bolt 4 and to the bolt 11, respectively. The drive also includes, the present instance, a light coil spring 12 in front of the stop nut 6 and pressing against a longitudinally slidable 7d sleeve 13 'Whose inner reduced end enters within the smooth bore of the pinion. This sprin tends to hold the pinion in disengage position but yields when the drive operates, that is, when the pinion 7 is caused to move outwardly into mesh with the engine member (which is here the fly-wheel 14) by reason of the longitudinal movement of the nut 8. The engaged position of the driving member and fly-wheel is illustrated 811) in Fig. 2.

For the purposes of my invention, I a ply to such drive a member located interme iate the fly-Wheel and the nut and adapted to cooperate with both of them in case of a backward rotation of the fly-wheel such as caused by a back-fire which cannot be held or restrained by the drive and its motor. This intermediate member comprises a roller 15 rotatable on an axis at right angles to the axis of the screw shaft and to the axis of the fly-wl1eel. It is mounted in a suitable manner inperpendicular position with respect to the screw shaft axis. In the present instance, it is provided with a stem 16 having a limited movement (which is yielding by virtue of the spring I7) in a bracket 18. This bracket is pivoted at 19 to a stationary bracket 20 secured in a suitable manner to the motor frame as by means of the bolts 21. The downward movement of the roller is Iimited by means of the colwheel.

lar 22 screwed to the end of the stem 16 and the upward movement of such roller is stopped by the contact thereof with the bracket 18 itself. The movable bracket 18 is held to the normal position shown in Fig. 1 against the shoulder 23 of the stationary bracket in a yielding manner as by means of the coil spring 24. In this normal position, the roller is held slightly away from the face of the fly-wheel so that there is clearance between them as shown in Fig. 1.

The roller 15 is provided with a cone face 25 which is'adapted to cooperate with a truncated cone periphery 26 of the control member or nut 8. The intermediate member or roller is normally free from all of the parts, except of course the hinged bracket in which it is mounted, and is held away from the face of the fiy-wheel by the tension spring 24. When the normal meshing opera tion of the driving memberoccurs, the control member or nut contacts the intermediate member or roller and the two cone shaped surfaces coming into contact causes a swinging of the roller against the face of the fiv- This lifts the roller upwardly against the compression spring 17 so that in the cranking operation the roller is yieldingly held in frictional contact with the fiywheel and with the cone surface or periphery of the nut but such roller performs no function during such normal cranking operation. In case of backward rotation of the fly-wheel such as may be caused by back-fire, the roller is rotated through its frictional contact with the fly-wheel in such direction as to cause the nut to be rotated at a speed greater than it is being driven by the screw shaft, with the result that the nut will be backed off and carried out of contact with the free-pinion 7, so that no load will be transmitted to the drive or the connected parts through the backward rotation of the fiy-wheel. 'In the case of what is known as a meeting back-fire, that is when electrical contact is made and current supplied to the motor when the fiy-wheel is in backward rotation and with the pinion in demeshed position, the nut will contact the roller and cause it, in turn, to contact the backwardly rotating fiy-wheel face before the pinion has been clamped between the control nut and the stop nut. As a re sult and in accordance with the mode of operation above described, the control nut will be screwed away or backed off along the screw shaft through the action of the roller.

I claim:

1. In an engine starter drive, the combination, with a member of the engine to be started, of a rotatable shaft, a driving member mounted thereon vfor enforced longitudinal movement thereon by the rotation of the shaft and adapted to engage the engine member, and means for relieving such driving member from such enforced longitudinal movement when the engine member rotates backwa dly.

2. In an engine starter drive, the combination, with a member of the engine to be started, of a rotatable shaft, a driving member mounted. thereon for enforced longitudinal movement thereon by the rotation of the Shaft and adapted to engage the engine member, and means for relieving such driving member from such enforced longitudinal movement when the engine member ro rates backvardly, such means comprising a member located between the engine member andthe driving member, and normally inoperative but cooperating therewith at the time of such backward rotation of the engine member. i

3. In an engine starter drive, the combination, with a member of the engine to be started, of a rotatable shaft, driving member mounted thereon for enforced longitudinal movement th'ereon by the rotation of the shaft and adapted to engage the engine member, and means for relieving such driving member from such enforced longitudinal movement when the engine member rotates backwardly, such means comprising a roller having one face to cooperate with the engine member and another face to cooperate with the driving member.

4. In an engine starter drive, the combination, with a member of the engine to be started. of a rotatable shaft, a driving member mounted thereon for enforced longitudinal movement thereon by the rotation of the shaft and adapted to engage the engine member, and means for relieving such driving member from such enforced longitudinal movement when the engine member rotates backwardly, such means comprising a roller having one face to cooperate with the engine member and another face to cooperate with the driving member, said roller being loosely mounted for free rotation and for limited longitudinal movement.

In an engine starter drive, the combination. with a member of the engine to be started, of a rotatable shaft, a driving member mounted thereon for enforced longitudinal movement thereon by the rotation of the shaft and adapted to engage the engine member. and means fOr relieving such driving member from such enforced longitudinal movement when the engine member rotates backwardly. such means comprising a roller having one face to cooperate with the engine member and another face to cooperate with the driving member, and a swinging bracket in which such roller is mounted to rotate.

6. In an engine starter drive, the combination, with a member of the engine to be started, of a rotatable shaft, a driving member mounted thereon for enforced lonae'raeee gitudinal movement thereon by the rotation the engine member and another face to cobracket, and a secon operate with the driving member, a swinging bracket in, which such roller is mounted for rotary and for longitudinal movement, and means for yielding holding the roller toward the driving mem r.

In an engine starter drive, the combination, with a member of the engine to be started, of a rotatable shaft, a driving member mounted thereon for enforced longitudinal movement thereon by the rotation of the shaft and adapted to engage the engine member, and means for relieving such driving member from such enforced longitudinal movement when the engine member rotates backwardly, such means comprising a roller having one face to cooperate with the engine member and another face to cooperate with the drivin member, a stationary bracket ivoted thereto, such roller being mounted for rotation in said second bracket.

8. In an engine starter drive, the combination, witha member of the engine to be started, of a rotatable shaft, a driving member mounted thereon for enforced longitudinal movement thereon by the rotation of the shaft and adapted to. engage the engine member, and means for relieving such driving member from such enforced longitudinal movement when the engine member rotates backwardly, such means comprising a roller having one face to cooperate with the engine member and another face to cooperate with the driving member, a stationary bracket, a second bracket ivoted thereto, and yielding means for hol ing the latterbracketin a normal position, such roller being mounted for rotation in said second bracket.

9. In an engine starter drive, the combination, with a member of the engine to be started, of a rotatable shaft, a driving member mounted thereon for longitudinal move ment thereof and rotary movement there with and composed of two parts, one a driving member proper adapted to engage the engine member and the other a control member operatively connected with the shaft and adapted to move the driving member proper along the shaft into engagement with the engine member, and means for moving such control member backwardly in event of back ward rotation of the engine member.

10. In an engine starter drive, the combination, with a member of the engine to be started, of a rotatable shaft, a driving mem ber mounted thereon for longitudinal movement thereof and rotary movement therewith and composed of two parts, one a driving member proper adapted to engage the engine member and the other a control member operatively connected with the shaft and adapted to move the driving member proper along the shaft into engagement with the engine member, and means for moving such control member backwardly in event of backward rotation of the engine member, said means comprising a rotatable member cooperating with the control member and with the engine member.

11. In an engine starter drive, the combination, with a member of the engine to be started, of a rotatable shaft, a dIlVlIl member mounted thereon for longitudinaImovement thereof and rotary movement therewith and composed of two parts, one a driving member proper adapted to engage the engine member and the other a control member operatively connected with the shaft and adapted to move the along the shaft into engagement with the engine member, and means for moving such control member backwardly in event of backward rotation of the engine member, said means comprising a rotatable member interposed between the control member and engine member and having surfaces adapted to control and cooperate with both of the two last named members.

12. In an engine starter drive, the combination with started, of a rotatable shaft, a (lIlVlIl member mounted thereon for longitudina movement thereof and rotary movement therewith and composed of two parts, one a driving member properadapted to engage the engine member and the other a control member, operatively connected with the shaft and adapted to move the driving member proper along the shaft into engagement with the engine member, and means for movin such control member backwardly in event 0backward rotation of the engine member, said means comprising a roller mounted to rotate on an axis at right angles to said shaft. and having a limited movement longitudinal of such axes, said roller being normally in the path of longitudinal movement of the control member and adapted to contact and be rotated by the engine member in its backwardrotation and thereby to rotate the control member.

13. In an engine starter drive, the combination, with a member of the engine to be started, of a rotatable shaft, a driving member mounted thereon for longitudinal movement thereof and rotary movement therewith and composed of two parts, one a driving member proper adapted to engage the a member of the engine to be driving member proper v lllli engine member and the other a control memrotate on an axis at right angles to said shaft and having a limited movement longitudinal of such axis, said roller having a periphery adapted to contact the eng ne member, and said control member and roller having cooperating cone surfaces.

14. In an engine starter drive, the combination, with a member of the engine to be started, of a rotatable shaft, a driving member mounted thereon for longitudinal movement thereof and rotary movement therewith and composed of two parts, one a driving member proper adapted to engage the engine member and the other a control member operatively connected with the shaft and m adapted to move the driving member proper along the shaft into engagement with the engine member, and means for moving such control member backwardly in event of backward rotation of the engine member, said means comprising a roller interposed be- "tween the engine member and control member, and a pivoted bracket in which the roller is mounted for rotation and for movement longitudinal of its axis, said roller hav-' ing surfaces cooperating with the engine member and control member.

15. In an engine starter drive, the combination, with a member of the engine to be started, of a rotatable shaft, a driving member mounted thereon for longitudinal movement thereof and rotary movement therewith and composed of two parts, one a driving member proper adapted to engage the engine member and the other a control member operatively connected with the shaft and adapted to move the driving member proper along the shaft into engagement with the engine member, and means for moving such control member backwardly in event of backward rotation of the engine member. said means comprising a roller interposed between the engine member and control member and a pivoted bracket "in which the roller is mounted for rotation and for movement longitudinal of its axis, said roller having surfaces cooperating with the en ine member and control member said ro ler being normally spring pressed towards and in contact with the control member.

16. In an engine starter drive, the combination, with a member of the engine to be started, of a rotatable shaft, a driving member mounted thereon for longitudinal movement thereof and rotary movement therewith and composed of two parts, onea driving member proper adapted to engage the engine member and the other a control member operatively connected with the shaft and 05 adapted to move the driving member proper along the shaft into engagement with the engine member, and means for moving such control member backwardly in event 01 backward rotation of the engine member, said means comprising a roller mounted to rotate on an axis at right angles to said shaft and having a limited movement longitudinal of such axis, said roller having aperiphery adapted to contact the engine member, and said control member and roller having cooperating cone surfaces and a spring for returning the driving member proper to normal position.

17. An engine starter drive including a rotatable shaft having a plain portion and a screw threaded portion, a driving member loosely mounted on said shaft for movement longitudinally on both said portions, a screw member threaded on the threaded portion and adapted to be automatically moved longitudinally by the rotation of said shaft and to contact the driving member and operatively connect it with the shaft for rotary movement therewith, an engine member with which the driving member is adapted to engage when moved longitudinally, and means controlled by the engine member in its backward rotation and acting upon the screw member to rotate the latter when the engine member is so rotated backwardly.

18. An engine starter drive including a rotatable shaft having a plain portion and a screw threaded portion, a driving member loosely mounted on said shaft for movement longitudinally on both said ortions, a screw member threaded on the t readed portion and adapted to be automatically moved Iongitudinally by the rotation of said shaft and to contact the driving member and operatively connect it with the shaft for rotary movement therewith, an engine member with which the driving member is adapted to engage when moved longitudinally, and means controlled b the engine member in its backward rotatlon and acting upon the screw member to rotate the latter when the engine member is so rotated backwardly, said means comprising a roller interposed between the engine member and the\ screw member and having surfaces adapted to contact with both of said last named members.

19. An engine starter drive including a rotatable shaft having a plain portion and a screw threaded portion, a driving member loosely mounted on said shaft for movement longitudinally on both said portions, a screw member threaded on the threaded portion and adapted to be automatically moved longitudinally by the rotation of said shaft and to contact the driving member and operatively connect it with theshaft for rotary movement therewith, an engine .member with which the driving member is adapted to engage when moved longitumemes dinally and means controlled by the engine member in its backward rotation and acting upon the screw member to rotate the latter when the enginemember is so rotated backwardly, said means comprising a roller interposed between the engine member and the screw member and having a periphery adapted to contact the face of the engine member and having at one end a conical friction surface, said screw member having a truncated conical friction surface adapted to cooperate with the cone surface of the roller. VINCENT BENDIX 

